package com.itheima.rgwm.filter;

import com.alibaba.fastjson.JSON;
import com.itheima.rgwm.common.BaseContext;
import com.itheima.rgwm.common.R;
import lombok.extern.slf4j.Slf4j;
import org.springframework.util.AntPathMatcher;

import javax.servlet.*;
import javax.servlet.annotation.WebFilter;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import java.io.IOException;

/**
 * 检查用户是否登录
 */
@WebFilter(filterName = "loginCheckFilter", urlPatterns = "/*")
@Slf4j
public class LoginCheckFilter implements Filter {
    //路径匹配器
    public static final AntPathMatcher PATH_MATCHER = new AntPathMatcher();
    @Override
    public void doFilter(ServletRequest servletRequest, ServletResponse servletResponse, FilterChain filterChain) throws IOException, ServletException {
        HttpServletRequest request = (HttpServletRequest) servletRequest;
        HttpServletResponse response = (HttpServletResponse) servletResponse;
        //1.获取本次请求的URI
        String requestURI = request.getRequestURI();
        log.info("拦截到请求：{}", requestURI);
        //定义不需要的路径
        String[] urls = new String[]{
                "/employee/login",
                "/employee/logout",
                "/backend/**",
                "/common/**",
                "/front/**",
                "/user/login",
                "/user/sendMsg",
                "/user/loginout",
                "/doc.html",
                "/webjars/**",
                "/swagger-resources",
                "/v2/api-docs"
        };
        //2.判断请求是否需要处理
        boolean check = check(urls, requestURI);
        //3.如果不需要处理
        if (check){
            filterChain.doFilter(request, response);
            return;
        }
        //4.判断是否登录，pc端
        if (request.getSession().getAttribute("employee") != null){
            log.info("用户已登录");

            Long empId = (Long) request.getSession().getAttribute("employee");
            //将用户id保存到工具类中
            BaseContext.setCurrentId(empId);
            filterChain.doFilter(request, response);
            return;
        }
        //4.判断是否登录，移动端
        if (request.getSession().getAttribute("user") != null){
            log.info("用户已登录");
            Long userId = (Long) request.getSession().getAttribute("user");
            //将用户id保存到工具类中
            BaseContext.setCurrentId(userId);
            filterChain.doFilter(request, response);
            return;
        }
        //5.未登录，返回登录界面
        log.info("用户未登录");
        response.getWriter().write(JSON.toJSONString(R.error("NOTLOGIN")));
        return;
    }

    /**
     * 路径匹配
     * @param urls
     * @param requestURI
     * @return
     */
    public boolean check(String[] urls,String requestURI){
        for (String url : urls) {
            boolean match = PATH_MATCHER.match(url, requestURI);
            if (match){
                return true;
            }
        }
        return false;
    }
}
